I mightve missed it but if not id also like to add one more point in favor of instance grinding.

It is often the case that there are 1 or 2 awesome items you can get from a quest that will last you a long while. However, as a rule, instance loot will always trump quest loot. Youll get a lot of crap doing instance grinding (have a DEer with you) but your peeps will also get some of the best items availalbe for their level as they level up.

Anyways, just a thought.